The research program of the California Primate Research Center will be focused in areas selected for relevance to human health. The research is broad in scope but emphasizes problems for which the nonhuman primate is the appropriate animal model. Investigations are carried out at the behavioral, physiological, biochemical and molecular levels. Studies of normal and abnormal functions are performed and spontaneous diseases as well as experimentally-induced disorders are investigated. There is a longstanding research interest in the adverse effects of environmental factors. Social dynamics are studied under field and laboratory conditions. The major program units will be Behavioral Biology (social organization, interspecies, differences, psychosocial development, maternal/infant behavior and development); Developmental and Reproductive Biology (gamete biology and fertilization, early embryonic differentiation and implantation, reproductive immunology, endocrinology and toxicology, contraceptive development); Respiratory Diseases (environmental oxidants and other air pollutants, cellular biology and molecular biology of the lung); Comparative Retrovirology (clinical and basic research in human and simian AIDS); Virology and Immunology (simian AIDS, pathogenesis, mechanisms of immunopathogenesis, lentiviruses, genetic determinants of immunosuppressive disease); and Comparative Primate Biology (hepatic physiopathology, comparative genetics, environmental physiology, intravital and quantitative microscopy and a variety of biomedical collaborative research projects). Primate Services (the major support unit, is composed of teams of specialists responsible for the high quality of animal care and ensures the humane treatment of animals. This unit also conducts studies to determine the most optimal approaches for handling and housing of animals in a research setting). There is considerable interaction between the research units, particularly the units for Comparative Retrovirology and Virology and Immunology.